Storvoll et al. (2005) present log data from 60 wells on the Norwegian Shelf to investigate velocity-depth trends in sedimentary rocks. They present an interesting analysis of, e.g., the sonic-log velocities of overpressured Jurassic sediments and of source rock intervals. The authors do, however, reach the conclusion that “no general velocity-depth function can be used when performing more accurate analyses like depth conversion of seismic data, pore-pressure prediction, or basin modeling” (Storvoll et al., 2005, p. 359). This conclusion is surprising for two reasons: first, because it is not tested by the authors, and second, because the article...